1、Frequency characteristic

The Microphone’s sensitivity is different when under different sound wave. It is currently high at a middle audio Frequency (eg: 1kHZ).But the Microphone’s sensitivity is low when at a low audio Frequency (eg: decades HZ )or a high audio Frequency (eg: thousands HZ).We take the sensitivity at the middle audio Frequency as the norm one,and defined the microphone’s Frequency characteristic as holding the sensitivity in a stated Frequency extension .When the Frequency characteristic is wider the microphone’ssensitivity to the wide frequency is higher, and the capability is better. When the perfect Microphone’s Frequency characteristic is between 20HZ and 20kHZ .

2、Directivity

Directivity is the characteristic when the microphone varied as the direction of the sound wave. And the Unidirectional just to be sensitivity to a directional sound, And to other directional hardly output.The omni-directional microphone can output almost the same when on the same acoustic stimulus and load condition form all direction.